1. Field of the Invention
This invention relates to chip scale packages and methods for manufacturing the packages at wafer level.
2. Description of Related Art
Miniaturization of electronic devices, which is one of major trends in the electronics industry, has led to the development of many technologies for manufacturing small packages, especially packages that have almost the same size as semiconductor integrated circuit chips. The Joint Electronic Device Engineering Council (JEDEC) has proposed the name ‘Chip Scale Package (CSP)’ for a type of small packages. JEDEC's definition of the CSP is a package having an outline that is 1.2 times or less than the outline of the semiconductor chip included in the package.
Many companies and institutes have developed their own CSP manufacturing technologies, and some have commercialized their own technologies or products. However, most of the newly developed CSPs have several drawbacks in the areas of product reliability, process reliability and manufacturing cost, when compared to plastic packages which are well established in the semiconductor industry. Therefore, for commercializing CSPs widely and successfully, new CSPs that have better process and product reliability and lower manufacturing costs are sought.